Q. At 18°C, a rod is exactly 20.00 cm long on a steel ruler. Both the rod and the ruler are placed in an oven at 285°C, where the rod now measures 20.21 cm on the same ruler. What is the coefficient of linear expansion for the material of which the rod is made?
Q. Suppose an electric field with a magnitude of 2.8 x 104 N/C at a certain location points due south. If a charge of -4.0 x 10-6 C is brought to the location, what is the electrostatic force that acts on this charge?